Q: A friend once insisted that “believe” and “think” carry different implications. For example:

If I “believe” that cats are better than dogs, she argued, I suspect it’s true. But if I “think” that cats are better than dogs, I’m certain it’s true.

Is there any truth to this distinction? If not, are the verbs completely interchangeable?

A: A person could parse out these subtleties of meaning. However, for the most part, these words are used by English speakers interchangeably.

In other words, it could be argued that “believe” means “to think it so” without the certainty of the word “think.” But it can also be argued, for instance, if someone were to say “I think it’s spelled that way,” that the someone is saying they “suspect” that’s the correct spelling.